I began by cutting my seed potato into three sections. You don't actually need to do this. A whole potato will grow just as well, but if you cut a seed potato into sections, each section will grow into its own plant. When cutting a seed potato, be sure that each piece has at least one eye, and preferably two or three.
I ran into some difficulty deciding what to do next. Some people tell you to leave the pieces out to dry for 24 hours before planting, while others go straight to planting them. I elected to wait the 24 hours, just to see what would happen.
The following day I gathered my supplies.
We're looking at a big bag of topsoil, chosen because it's pretty much the same thing as garden soil, just cheaper. I like that cost benefit. My potatoes are above it, followed by scissors, in a counter clockwise direction. Below that you can see my reusable bag, which is finally coming to some good use again. Last, we have a watering can. Potatoes need to stay moist.
Unless we include the knife that I used to cut the potatoes, these are all the supplies you need to create a grow bag of your own. Simple!
I started the second part of this DIY project by cutting the handles off of my bag, simply to keep them from getting in my way. They have no real purpose in this project, anyway.
I also cut cut lines about 1/2" to 1" long along the bottom, as well as the lower sections of each side, in order to ensure proper drainage. Potatoes need to be kept in moist soil, but they don't want to be in a bog, after all! Last, I folded down the sides of the bag by about four inches. This was done both to keep the bag in a stable position, as well as to ensure enough sunlight gets to the soil.
Finally, I filled the bag with about 3 1/2 inches of soil and dropped the potato pieces inside, ensuring an ample amount of space between each section. Technically, you should fill the bottom with 3-4" of compost or decomposing leaves, but I was out of luck there, since my compost is inundated with black walnut tree detritus, which would kill off my potatoes in a heartbeat, due to the trees phytotoxin. So I just used soil. I'll need to buy an organic fertilizer to provide proper nutrition to the plants.
At this point I added some water to the soil to ensure it was properly moistened. The soil I had chosen was already pretty moist (something I'm not used to, being from the desert southwest) so I didn't have to add much. Use your best judgement when you get to this point.
Last, I added more dirt. I added about 3" of it, in order to completely cover my potato sections, as well as have another 1-1/2" above them. Again, this is another "use your best judgement" step. The amounts of soil covering the potatoes in the various sites I visited ranged from 'just enough to cover the tops' to '3-4".' I elected to stick to the middle ground.
I then watered my grow bag one last time, to ensure the top didn't dry out.
And we're done! Now all we do is wait until little tubers start sticking out of the soil. When that happens, I'll need to go through the process of adding enough soil to cover them again. This step gets repeated until the sides of the bag are totally unrolled, and no more soil can be added. I think the reason for this is to strenthen the stems of the plants, but in all honesty, I don't know for sure.
Potatoes are harvested when the leaves start to wilt and the plant generally looks pretty nasty. You then simply dump out the soil and collect all of the potatoes that have been growing inside, and as a bonus, you can replant one or two of them to produce a new potato crop!